Personal computers, along with their monitors, are used in nearly every field of work. Many fields also make use of microprocessors for encoding and decoding video signals. Often times, it is desired to display video content that was originally created for television on a computer monitor. However, television video signals and the video formats of most computer displays are not the same. Computers commonly use a non-interlaced video display format, also called progressive scan. With progressive scan, an entire video frame is scanned line-by-line, typically from top to bottom, to appear on the computer display. The process repeats and rescans the entire frame at a given refresh rate.
In contrast, many sources of consumer video, such as television signals, use an interlaced display format. An interlaced video frame contains two fields. The first field consists of the odd lines in the interlaced video frame and the second field consists of the even lines in the interlaced video frame. When displayed on an interlaced video system, the lines of the two fields are displayed in an alternating fashion. All odd lines of the interlaced video frame are displayed, and then all even lines of the interlaced video frame are displayed.
The use of interlaced display format is still quite common in video products. In a system that aims to display an interlaced video signal on a progressive scan monitor (or other non-interlaced display), a deinterlacing method is applied to adapt the interlaced format. Current generations of video processors deinterlace video by using a variety of techniques.
One field of prior art techniques includes intra-field processing (or spatial-only domain processing) such as bob. Another field of prior art techniques includes inter-field processing (or spatial and temporal domain processing) such as weave, motion adaptive, and motion compensation. The bob and weave techniques are typically applied due to their inherently simple complexity, but at the cost of picture quality. For instance, the bob technique determines an average of the pixels directly above and below (e.g., at 90 degree angles) a pixel being estimated for deinterlacing. This is a simple technique but can lead to reduced picture quality. The motion adaptive and motion compensation techniques achieve a better picture quality, but with a more expensive operation.
Spatial-only deinterlacers are applied in environments that cannot access temporal reference pictures and require minimal complexity. However, conventional spatial deinterlacer techniques, such as bob, fail to provide sufficient picture quality due to the lack of proper angle detection beyond the vertical 90 degree angle typically utilized by the bob technique. A simple and efficient technique to deinterlace interlaced pictures in a quality manner for a spatial-only domain would be beneficial.